One new concept in Chrome is the idea of an incognito session, where the history and cookies are not preserved. This could be useful if, for example, you’re at a friend’s house or an Internet café, or if you don’t want your spouse to see that you’ve been shopping for a surprise birthday present. Or other things.

To start a new incognito session in Chrome, just press Ctrl+Shift+N. A new window appears, with slightly different coloring and a “secretive browser person” icon at the top.

(To close the incognito session, just press Alt+F4 as you normally would to close a program. All tabs in your new window close at once.)

Google Chrome was released in beta today (Tuesday, September 2). This is Google’s browser, currently only for Windows, and its arrival rekindles the browser wars into a three-way race between Mozilla’s Firefox, Microsoft’s Internet Explorer, and now Google’s Chrome.

Chrome offers much faster loading speed and more stability as its main differentiators, but also a new feature called an “incognito session” (which we’ll cover later today), plus the ability to quickly use web sites (such as Gmail) as applications on your desktop and Start menu.

Ctrl+K or Ctrl+E to search does still work too, but not quite in the same method as Firefox: It simply moves you up to the omnibox with a question mark pretyped, which will then allow you to type in your search term and press Enter to get a search result. (You cannot choose a specific search engine with Alt+Down Arrow as you can with Firefox.)

Ctrl+S does nothing instead of saving the current web page, although you can right-click (even with Shift+F10) and choose “Save as” from the shortcut menu.

At least one keyboard command, Ctrl+O to open a file, has no listing anywhere on any menu. (All keyboard shortcut commands should have toolbar icons or menu entries as equivalents, and those icons or commands should always list the keyboard shortcut as a visual reminder.)

When Chrome offers to save a password when you log in to a site, there’s no keyboard method to say yes or no — you have to click on one of the buttons that appear.

You can’t navigate your saved bookmarks in a menu to select a site as you can with Firefox’s bookmark menu. (In Chrome, you can only click on the bookmark toolbar under “Other bookmarks” or search bookmarks in the omnibox using Ctrl+L and typing in a few letters from the bookmark.)

Here are some of the Firefox keyboard commands that do NOT work in Chrome: